scholarly journals Epimerite-Host Epithelium Relationships among Eugregarines Parasitizing the Damselflies Enallagma civile and Ischnura verticalis

2001 ◽  
Vol 87 (5) ◽  
pp. 988 ◽  
Author(s):  
T. J. Percival Cook ◽  
J. Janovy ◽  
R. E. Clopton
1994 ◽  
Vol 40 (9) ◽  
pp. 775-780 ◽  
Author(s):  
Andrea R. Tilden ◽  
Wendy J. Anderson ◽  
Victor H. Hutchison

2006 ◽  
Vol 120 (4) ◽  
pp. 413 ◽  
Author(s):  
Paul M. Catling ◽  
Raymond Hutchinson ◽  
Paul M. Brunelle

During late summer and autumn, in the Baie des Chaleurs region of Quebec, 18 species of adult dragonflies were recorded during one or more visits of at least 2 hours each to 14 saltmarshes. Three species, Aeshna canadensis, Sympetrum danae and S. internum, were present in more than half of the sites. The most abundant species was S. internum with over 100 seen at some locations. Adults of several species, including Aeshna canadensis, A. umbrosa, Enallagma civile, E. hageni, Ischnura verticalis, Lestes disjunctus, Libellula quadrimaculata, Sympetrum danae, S. internum and S. obtrusum, occurred in relatively high frequencies in both Baie des Chaleurs saltmarshes and in those elsewhere in Acadia. Within Baie des Chaleurs observations of emergence and/or presence of larvae, as well as regional abundance, were recorded for Aeshna canadensis, A. umbrosa, Ischnura verticalis, Sympetrum costiferum, S. internum and S. vicinum. Oviposition in saltmarsh pools was recorded for Aeshna canadensis, Enallagma civile, E, hageni, Ischnura verticalis, Lestes congener and Sympetrum danae. The saltmarsh dragonfly fauna of Baie des Chaleurs is significantly different from that of the rest of Acadia based on frequencies predicted from the latter region. To a large extent this difference is a result of significantly increased use of saltmarsh habitat by adults of six species including Lestes congener, Sympetrum danae, Aeshna canadensis, Sympetrum costiferum, Lestes disjunctus, and Sympetrum internum (in order of decreasing significance) in Baie des Chaleurs in comparison with saltmarshes elsewhere in Acadia. Local amelioration of salty conditions in certain saltmarshes, superimposed on regional amelioration as a result of protection from storms and saltwater dilution in the Baie des Chaleurs estuary, may contribute to an environment where adaptation can occur or where already tolerant species can exist. Dragonflies use saltmarsh habitat on the northeast coast of North America more extensively than is currently documented.


2011 ◽  
Vol 143 (5) ◽  
pp. 460-469 ◽  
Author(s):  
Julia J. Mlynarek ◽  
Daniel G. Bert ◽  
G. Haydeé Peralta-Vázquez ◽  
Joanna A. James ◽  
Mark R. Forbes

AbstractAlthough human-modified landscapes are characterized by the loss of natural habitats, new habitats also can be created and exploited by many species. The importance of landscape change to invertebrate associations (particularly host-parasite associations) is understudied. Our objective was to determine whether prevalence and intensity of gregarine parasitism in the damselfly Ischnura verticalis (Say) (Odonata: Coenagrionidae) differed between 17 artificial and 7 natural wetlands in landscapes that varied in amount of forest and wetland cover and road density determined at spatial extents of 500m and 1km from each wetland. Wetlands were located in and around Ottawa, Ontario, and Gatineau, Quebec, Canada. Wetland type did not account for significant variation in principal components based on forest and wetland cover and road density at either spatial extent. Gregarine prevalence was higher in damselflies collected from natural wetlands than in those collected from artificial wetlands and was positively associated with increasing forest cover. In contrast, gregarine intensity was inversely related to road density. Our results suggest that parasitism of damselflies by gregarines is associated with wetland type and landscape characteristics, although the mechanisms producing such relationships are unknown.


2020 ◽  
Vol 21 (18) ◽  
pp. 6586
Author(s):  
Rihab Nasr ◽  
Ali Shamseddine ◽  
Deborah Mukherji ◽  
Farah Nassar ◽  
Sally Temraz

Gastric cancer is the end result of a complex interplay between host genetics, environmental factors, and microbial factors. The link between gut microbiome and gastric cancer has been attributed to persistent activation of the host’s immune system by gut microbiota. The end result of this dysregulated interaction between host epithelium and microbes is a state of chronic inflammation. Gut bacteria can promote anti-tumor immune responses through several mechanisms. These include triggering T-cell responses to bacterial antigens that can cross-react with tumor antigens or cause tumor-specific antigen recognition; engagement of pattern recognition receptors that mediate pro-immune or anti-inflammatory effects or via small metabolites that mediate systemic effects on the host. Here we review the role of the gut microbiome including H. pylori and non-H. pylori gastric bacteria, the immune response, and immunotherapy using checkpoint inhibitors. We also review the evidence for cross talk between the gut microbiome and immune response in gastric cancer.


2019 ◽  
Vol 49 (1) ◽  
pp. 230-237
Author(s):  
S M Starr ◽  
N E McIntyre

Abstract Current climate projections for the Great Plains of North America indicate markedly increased air temperatures by the end of the current century. Because the Great Plains contains >80,000 intermittent wetlands that serve as irreplaceable wildlife habitat, this projected warming may have profound effects throughout a continental-scale trophic network. However, little research has been done to determine how projected warming may affect the growth, development, or survival of even common species in this region. We conducted laboratory warming experiments, using an abundant amphibious predatory insect, Enallagma civile (Hagen, 1861), as a model organism, to determine whether projected warming may affect development or survival. Eggs were collected and reared under four water temperature regimes representing current (26°C) and projected future conditions (32, 38, and 41°C). Nymph body size after each molt, development rate, and deaths were recorded. Elevated water temperatures were found to significantly affect the survivorship of E. civile eggs and nymphs as well as adult body size at emergence: an increase in temperature incurred a decrease in survival and size. Nymphs in the two hotter treatments were smaller and had low survivorship whereas individuals in the cooler temperatures generally survived to adulthood and were larger. Nymphs reared at 32°C experienced accelerated ontogenetic development compared with the other temperatures, going from egg to adult in 26 d. Projected elevated temperatures may, thus, be both advantageous and detrimental, causing concern for aquatic invertebrates in this region in the future.


2017 ◽  
Vol 8 (4) ◽  
pp. 625-633 ◽  
Author(s):  
N. Calonghi ◽  
C. Parolin ◽  
G. Sartor ◽  
L. Verardi ◽  
B. Giordani ◽  
...  

Vaginal lactobacilli offer protection against recurrent urinary and vaginal infections. The precise mechanisms underlying the interaction between lactobacilli and the host epithelium remain poorly understood at the molecular level. Deciphering such events can provide valuable information on the mode of action of commensal and probiotic bacteria in the vaginal environment. We investigated the effects exerted by five Lactobacillus strains of vaginal origin (Lactobacillus crispatus BC1 and BC2, Lactobacillus gasseri BC9 and BC11 and Lactobacillus vaginalis BC15) on the physical properties of the plasma membrane in a cervical cell line (HeLa). The interaction of the vaginal lactobacilli with the cervical cells determined two kinds of effects on plasma membrane: (1) modification of the membrane polar lipid organisation and the physical properties (L. crispatus BC1 and L. gasseri BC9); (2) modification of α5β1 integrin organisation (L. crispatus BC2, L. gasseri BC11 and L. vaginalis BC15). These two mechanisms can be at the basis of the protective role of lactobacilli against Candida albicans adhesion. Upon stimulation with all Lactobacillus strains, we observed a reduction of the basal oxidative stress in HeLa cells that could be related to modifications in physical properties and organisation of the plasma membrane. These results confirm the strictly strain-specific peculiarities of Lactobacillus and deepen the understanding of the mechanisms underlying the health-promoting role of this genus within the vaginal ecosystem.


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